Hardlinks won't really work as a snapshot substitute; any files that are modified (rather than deleted/rewritten) will be modified in the "snapshot" as well. A hardlink "snapshot" like that would protect against accidental deletion, but that's about it.

No. The reason it does not exist is because the Ares-I kept running into delays and cost overruns, as well as performance issues that continually forced them to remove capabilites for Orion. The reason it _shouldn't_ exist is that it's a _terrible_ program that, had it been allowed to continue, would quite probably have killed NASA and never gotten us out of LEO anyway. Even the Ares-I would not have been operational during Obama's presidency, even presuming he stays in office until 2016.I used to be a fan of Constellation when all I knew was the current NASA PR. After learning just what an absolute mess the program really was, and the severe issues with the Ares-I, I've changed my mind. While the Ares-I would probably be possible to finish, the expected cost of development is $35 billion dollars, and not before 2017. And at the end of all that time and money, you end up with a rocket that takes less mass to LEO than the Falcon 9 Heavy will - and the F9H will have cost roughly as much to fully develop from scratch as the Ares-I's expected yearly recurring operating cost.It is also worth pointing out that the budget that cancels Constellation is NOT in effect yet, and won't be until next year; congress still has to approve it. Obama has absolutely nothing to do with the current delays and failings of the Constellation program - the program itself, and the previous NASA administrator, bear all the blame for that.

Though it's increasinly rarely used by regular consumer, RS232 is still very much around, and I'd argue it's not even technically "obsolete", since at least for one of its purposes - low-level kernel debugging/troubleshooting/development - none of the new standard ports that can do what it does for that purpose.